隨著生醫電子應用的快速發展，將晶片穿戴或植入人體用以偵測各種生理訊號或是進行藥物釋放成達到居家照護的目的將成為趨勢。由於此類晶片的電源來源為電池、體熱發電或是無線電能量收集電路，因此在其傳輸介面電路設計上最重要的要求為超低功率消耗，以達到延長使用壽命的目的。由於接收器必須長時間維持開啟狀態，因此接收器的功率消耗佔了整體功率消耗的一半以上，因此實現一超低功耗接收器可大幅延長使用時間。 在超低功耗電路設計方面，無論類比或數位電路近年來皆利用將電晶體操作在次臨界區達到降低功率消耗的目的。在類比與射頻電路設計上，Christian C. Enz進一步的將次臨界區分為弱反轉區與中反轉區。並由其研究顯示當操作速度小於100MHz時，將電晶體操作在弱反轉區時可以達到超低功率消耗之目的，電晶體亦具有提供20dB本質增益之能力。 在此我們實現了一個以人體為傳輸介質應用於穿戴式或植入式生理訊號感測器之超低功耗接收器前端電路。由於以人體為傳輸介質，因此傳輸的路徑損耗會比空氣中小許多，大幅降低對接收器前端電路靈敏度之要求。電路中電晶體皆操作在深弱反轉區，在無輸入訊號下，電路之靜態電流消耗僅35.4uA，此時操作電壓為1.8V，亦靜態功率消耗僅68.4uW。當操作在400MHz輸入訊號下，在僅消耗86.4uW下達到24.1dB之電壓增益表現、大於18dB之訊號、三階失真比與大於200KHz之輸出頻寬。As age advances, the electronic applications in the biomedical develops rapidly. It is the trend that people carry chips or implant chips into their body in order to detect a variety of physiological signals. Also, they use chips to release medicines to achieve the purpose of home care. As those chip’s power source used for the battery, the power generation of body heat or radio energy harvested circuit, therefore the most important requirements in transmission interface circuit design for ultra-low power consumption to extend the service life of purpose. Since the receiver must remain turn on for a long time, the receiver''s power consumption accounted for more than half of the overall power consumption, therefore to achieve an ultra-low power receiver can significantly extend the used time. In ultra-low power circuit design, whether analog or digital circuits are using transistors operating in subthreshold to reduce power consumption in recent years. In analog and RF circuit design, Christian C. Enz further divided sub-threshold into the weak inversion and the moderate-inversion. His studies shows that when the operating speed less than 100MHz, people operated the transistor in weak inversion in order to achieve the purpose of the ultra-low power. Transistors also provide 20dB intrinsic gain. We have accomplished an intra-body communication in wearable or implantable type of physiological signal sensor on ultra-low power receiver front-end circuit. Because transmission medium is human body, the path lose is smaller than in the air. It substantially reduced the requirements on the sensitivity of receiver front-end. All transistors are operating on deep weak inversion. Without input of the RF signal, the receiver front-end consumes a static current of 35.4 μA under a supply voltage of 1.8 V, also static power consumption is only 68.4 μW. When input signal is 400 MHz, the power consumption is only 86.4 μW, the voltage gain has 24.1 dB, IIP3 has greater than 18 dB, and bandwidth is 200 KHz.